JPH0318105Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a clamping device for clamping a workpiece having a flange or the like, such as a transmission case of a vehicle, when the workpiece is machined.

(Prior art) Conventionally, when attaching a workpiece such as a transmission case that is flange-bonded to an engine to a workpiece mount for machining, a plurality of workpiece clamps positioned around the outer periphery of the flange portion of the workpiece are attached to the workpiece mount. It is generally widely practiced to firmly hold a workpiece on a workpiece mount by clamping it with pressure using a device.

However, the clamping position of each of the above-mentioned clamping devices on the workpiece mounting base is usually always set at the same location, so if the shape of the workpiece is different,
Some of the plurality of clamping devices may not be able to sufficiently clamp the workpiece, and the clamping state of the workpiece to the mounting base becomes unstable. For this reason, a dedicated workpiece mount with a different clamp position is prepared for each workpiece with a different shape, but in that case, each time the shape of the workpiece changes, the workpiece mount must be replaced with a corresponding one. However, there was a problem in that this replacement work took time and reduced work efficiency.

Therefore, in order to solve the above-mentioned problems, a dovetail-shaped sliding groove is provided in the workpiece mounting base, and tightening is performed in the sliding groove, as disclosed in, for example, Japanese Utility Model Application Publication No. 60-91335. While the lower end of the tool is slidably fitted, a long hole is provided in the clamp arm that clamps and unclamps the workpiece, and the upper end of the fastener is loosely fitted into the long hole. It has been proposed that the clamping position of the clamp arm can be varied depending on the work by adjusting the position relative to the moving groove and the elongated hole.

(Problem to be solved by the invention) However, with the above-mentioned conventional method, although the clamp position can be freely changed for workpieces of different shapes, the change operation requires the use of a tightening tool as described above. The position of the clamp arm must be adjusted each time with respect to the sliding groove and elongated hole, and furthermore, in order to fix the adjusted position, it is necessary to screw a nut onto the upper end of the clamping tool and tighten the clamp arm. Changing the clamp position takes time and reduces work efficiency in another aspect, making it unsuitable for mass production.

The present invention was devised in view of the above, and its purpose is to divide the conventional clamp arm into two parts, an arm body and a clamp claw, and to rotate the clamp claw with respect to the arm body. By making positioning possible, the clamp position for workpieces of different shapes can be freely changed and set with simple operations.
The aim is to improve practical work efficiency for workpieces.

(Means for solving the problem) In order to achieve the above object, the solution of the present invention is to provide a clamp arm supported swingably in the direction of clamping and unclamping the workpiece on the workpiece mounting base, A claw member is provided at the tip of the clamp arm to press and clamp the workpiece by its clamping action. Furthermore, an engagement support means is provided which engages and supports the claw member on a spherical surface while being rotatable in a direction perpendicular to the clamping direction while the claw member is biased against the clamp arm. Further, a rotation positioning means is provided for positioning the rotational position of the claw member in a plurality of stages at a position away from the engagement support portion of the engagement support means.

(Function) With the above configuration, in the present invention, the workpiece is clamped against the workpiece mounting base by the clamping action of the clamp arm with the claw member provided at the tip thereof.

In this case, the claw member is engaged and supported by the engagement support means so as to be rotatable with respect to the clamp arm in a direction perpendicular to the clamping direction, and the rotation position is positioned in a plurality of stages by the rotation positioning means. Therefore, even if the workpiece has a different shape, by changing the rotation position accordingly, the clamping position can be freely changed and set depending on the workpiece, and thus the workpiece can be held and fixed on the mounting base. Operation can be performed easily and reliably, and work efficiency can be improved.

In addition, since the claw member is engaged and supported on a spherical surface while being urged against the clamp arm by the engagement support means, there is no possibility that force associated with the clamping may act on the engagement support part. Thus, the durability of the engagement support portion is improved.

(Example) Hereinafter, an example of the present invention will be described based on the drawings.

In FIG. 1, reference numeral 1 denotes a substantially disk-shaped workpiece mount arranged so that the workpiece receiving surface 1a is vertical, and 2, 2, . . . indicate a plurality of workpieces ( A workpiece clamping device according to an embodiment of the present invention (only one of which is shown in the figure), W is a transmission of an automobile as a workpiece that is fixedly held on the workpiece receiving surface 1a of the mounting base 1 by each of the clamping devices 2. It is a case.

Each of the clamp devices 2 includes a clamp arm 3 supported on a mounting base 1 so as to be swingable in the direction of clamping and unclamping the mission case W. A first bracket 5 has a mounting portion 4 protruding from the workpiece receiving surface 1a of the mounting base 1.
The work piece is supported via a support shaft 6, and is arranged with the base end of the arm protruding outward from the workpiece receiving surface 1a and the distal end of the arm facing toward the middle of the workpiece receiving surface 1a.

Further, a fluid pressure cylinder 7 is attached to the outer circumferential back surface of the mounting base 1 via a second bracket 8 protruding from a position corresponding to the first bracket 5, and a piston rod 7a of the fluid pressure cylinder 7 is attached.
A proximal end portion of the clamp arm 3 is pivotally attached to the distal end, and the clamp arm 3 is swung about a support shaft 6 as a fulcrum by the expansion and contraction of the fluid pressure cylinder 7.

On the other hand, branch parts 12 and 13 are formed at the distal end of the clamp arm 3, and the branch parts 12 and 13 are bifurcated in a direction perpendicular to the clamp direction. A claw member 9 that presses and clamps the mission case W against the mounting base 1 is held by these members. At the tip of the claw member 9, as shown in enlarged detail in FIGS. 2 and 3, there is a first clamp part 10 (first clamp part 10) that comes into contact with the flange part w of the mission case W and presses and clamps it. (the one on the right in Figure 2) and the second
The clamp part 11 (the one on the left side in FIG. 2) is formed by bifurcating, and the first clamp part 10 is provided longer than the second clamp part 11.

Further, a stepped hole 14 that opens in the unclamping direction is formed in the branch portion 13 on the mounting base 1 side at the tip of the clamp arm 3, and an engagement support member 16 is inserted into the hole 14 so that the tip thereof is connected to the hole. 14 and is housed in such a way that it protrudes between both branch parts 12 and 13 and is biased in the unclamping direction by the spring force of a spring 15. The distal end of the engagement support member 16 has a convex spherical surface, and the distal end is engaged with an engagement recess 17 formed at the end of the claw member 9 and having a concave spherical surface. The support member 16, the spring 15, and the engagement protrusion 17 allow the claw member 9 to be rotated in a direction perpendicular to the clamping direction while being biased against the clamp arm 3, and are engaged and supported on a spherical surface. An engagement support means 18 is configured.

Further, in the branch portion 13 of the clamp arm 3, a hole portion 19 that opens in the unclamping direction is formed closer to the tip than the engagement support member 16, similar to the stepped hole portion 14. Part 19
A ball 21 is housed in the hole 19 and is biased by a spring 20 so that a portion of the ball 21 protrudes from the hole 19 into the branch parts 12 and 13. On the other hand, the pawl member 9 has three engagement switching recesses 22, 22, 2 on a rotation locus that revolves around the engagement support member 16 and passes over the ball 21 on the arm 3 side.
2 are formed at a predetermined interval, and by switching the engagement of the claw member 9 to the clamp arm 3, the rotational position of the claw member 9 can be changed to the engagement support member 1.
A rotary positioning means 23 is configured to position at a predetermined angle in three steps at positions apart from 6.

Therefore, in the above embodiment, the clamp arm 3 swings due to the expansion/contraction operation of the fluid pressure cylinder 7, and the mission case W is clamped/unclamped with respect to the workpiece mounting base 1 by the claw member 9 at the tip thereof. However, the claw member 9 has a clamp position of 3.
Since the positioning is changed in stages, when clamping the transmission cases W with different shapes for machining as shown by the imaginary lines in FIG. The mission case W can be reliably held and fixed on the mounting base 1 with a single touch by a simple operation of rotating, thereby improving work efficiency.

The claw member 9 is engaged with and supported by an engagement support member 16 biased by the spring force of a spring 15 with respect to the clamp arm 3, and also engages and supports an engagement recess 17 at the base end of the claw member 9. Since it is engaged with the convex spherical surface at the tip of the member 16, even if the force associated with clamping is applied to the engagement support part, no kink will occur, thereby improving the durability of the engagement support part. I can do it.

In the above embodiment, the clamp parts 10 and 11 of the claw member 9 are made into a bifurcated shape with different lengths so that they can be switched and used according to changes in the shape of the mission case W. However, the present invention is not limited to this. For example, it is also possible to omit one of the clamp parts 10 and 11 or to form a three-pronged configuration with three clamp parts.

Further, in the above embodiment, a case has been shown in which the rotational position of the claw member 9 is determined in three stages, but the present invention is not limited to this, and it is also possible to adopt two stages or four or more stages.

Further, in the above embodiment, the distal end of the clamp arm 3 is bifurcated and the proximal end of the claw member 9 is inserted between the branched parts 12 and 13, but the connection relationship is not limited thereto. It is also possible to form the proximal end of the member into a bifurcated shape and insert the distal end of the clamp arm 3 between the bifurcated portions to create a connection relationship opposite to that of the above embodiment. In the above embodiment, the transmission case W is shown as the workpiece, but it goes without saying that the workpiece is not limited to this.

(Effect of the invention) As explained above, according to the invention, the claw member on the clamp arm can be freely rotated in a direction perpendicular to the clamping direction and engaged and supported on a spherical surface while being biased against the clamp arm. At the same time, the rotational position of the claw member can be engaged and switched in multiple stages, so the clamping position can be freely changed and set for workpieces of different shapes with a single touch operation. It is possible to securely hold and fix the workpiece and improve work efficiency. Furthermore, even if the force associated with clamping is applied to the engagement support part, no kink will occur, and the durability of the engagement support part can be improved.

[Brief explanation of the drawing]

FIG. 1 is a side view showing a work clamping device according to an embodiment of the present invention, FIG. 2 is an enlarged front view of the same main part,
FIG. 3 is a sectional view taken along the - line in FIG. 2. DESCRIPTION OF SYMBOLS 1...Work mounting base, 2...Work clamp device, 3...Clamp arm, 9...Claw member, 16
...Engagement support member, 18...Engagement support means, 20
... Spring, 21 ... Ball, 22 ... Engagement switching recess, 23 ... Rotating positioning means, W ...
transmission case.

Claims (1)

[Scope of utility model registration request] a clamp arm supported swingably in the direction of clamping and unclamping the workpiece on a workpiece mounting base; a claw member provided at the tip of the clamp arm to press and clamp the workpiece by the clamping action of the clamp arm; An engagement support means that engages and supports the claw member on a spherical surface so as to be rotatable in a direction perpendicular to the clamping direction while the claw member is biased against the clamp arm, and an engagement support portion of the engagement support means. A work clamping device comprising: rotational positioning means for positioning the rotational position of the claw member in a plurality of stages at a position away from the workpiece clamping device.